Empty err Object when sending POST request to /ITrade/SendOffer/v1/ [Node.js]

[ghost]

Sometimes it works fine, sometimes node server needs to be restarted in order to it to work.

Code:

const rp = require('request-promise');
module.exports = function(uid, token, items, code, key) {
    let promise = new Promise((resolve, reject) => {

    let options = {
        method: 'POST',
        uri: 'https://api-trade.opskins.com/ITrade/SendOffer/v1/',
        body: {
            key:  key,
            twofactor_code: code,
            uid: uid,
            token: token,
            items:  items
        },
        json: true
    };

    rp(options)
        .then((body) => {
            resolve(body.response);
        })
        .catch((err) => {
            // Here I get empty object in 'err' in 40% of my requests
                        console.log(err);
        });

    });

    return promise;
}